SCIENTIFIC EVIDENCE
Isoinertial training
Isoinertial, the origins
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Inertial training is a training method that originated in the mid- 1980s . Initially conceived for astronauts who needed to train in orbit to maintain muscle tone and to exercise against resistance , it then also developed in sports and, finally, physiotherapy and rehabilitation.
The flywheel was designed by Dr. Archibald V. Hill . In 1922 Dr. Hill introduced the so-called inertial flywheel, a heavy wheel that rotating on its own axis could reach a high speed and offer a more optimal execution and greater mechanical efficiency in high intensity requests. Dr. Hill marks the breakthrough, but as mentioned earlier, it wasn't until the mid-1980s that Hans Berg and Per Tesch published a series of papers using the well-known isoinertial methodology. Dr. Per Tesch, recently in 2017, analyzed in the article Clinical Applications of Iso-Inertial, Eccentric-Overload (YoYo â„¢) Resistance Exercise the whole history of the method highlighting its effects.
But how does it work?
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Inertial training represents a new concept of muscle training that uses machines with a resistance created by a mass set in rotation by the user's movement.
This mass is represented by a flywheel (or inertia) , which is wound with an inextensible rope .
This string is adjusted according to the length of the movement to be performed in order to store speed during the concentric phase of the movement.
In the concentric phase the string is completely pulled, and then rewinds around the central shaft during the eccentric phase. The greatest work you have is during the eccentric phase of the movement, in which you have to oppose the force with your own muscle activation.
The method, in the sports field, has seen its great use thanks to the Spanish studies of Tous which highlighted how this tool was useful for creating an eccentric overload during exercise.
Research has explained to us that in order to use this technology correctly, the athlete must apply maximum force during the concentric phase of the action. The inertial device, therefore, will produce a counter force that must be countered and controlled by the athlete in the eccentric phase of the movement without an interruption.
According to Tesh, 2004, the eccentric benefit will be obtained only if the athlete accompanies the car in the first two thirds of the joint stroke, and then applies maximum braking force in the last third of this phase.
Norrbrand (Norrbrand, 2008) of the Karolinska Institutet studied the method with knee extension exercises against one gravitational and the other inertial resistance. The study demonstrated a better relationship in the development of force between the concentric and eccentric phases of action in the inertial device with notable adaptations in the eccentric phase.
The relationship between the phases of movement and the development of one or more properties of the athlete, during an activity
with isoinertial aids, they have been studied by numerous scientists and trainers.
Among the many we mention:
Askling (2003) : In his study, he used the YoYo squat (Sweden) with a 4x8rep protocol. finding a significant increase in power in the test performed with this type of training.
De Hoyo (2015) , developed a strength training program: 10 weeks with young soccer players in the sub-17 and sub-19 categories, distributed in a control group (they did not do any kind of strength work, only technical training and tactical) and an experimental group. As desirable the experimental group, with a training frequency of between 1 and 2 sessions per week (3-6 sets of 6 repetitions), achieved better results in terms of injury prevention and also showed improvements in the ability to jump and sprint. .
Maroto-Izquierdo (2017) , developed a 6-week training protocol with a YoYo leg press machine (Sweden). Improvements were achieved in the maximum dynamic resistance of the quadriceps, in the MVC at different loads, in the vertical jump and in the acceleration test over 20 meters.
As for the work of Maroto-Izquierdo (2017) are two important successive Review.
The two scholars supported the idea that isoinertial work achieves superior adaptations in terms of strength, power, and levels of hypertrophy, in both healthy subjects and athletes. The advantages of working with this methodology were described, with actions developed at maximum intensity and their improvements also in quality more functional to sports performance.
However, in the review work by Vicens-Bordas (2018) , the authors explained how strength training , using inertial flywheels, cannot be identified as superior to traditional training.
The authors criticized the work of Maroto-Izquierdo (2017), arguing that several studies used in this latest review did not really compare inertial training and traditional (gravitational) training. According to Vicens-Bordas (2018), further studies, preferably RCTs, are needed to reach some conclusions.
There are numerous studies on this topic that are moving around Spacewheel and other isoinertial mechanisms. A different point of view is provided to us by RM Capello , Technical Director at EYGEA, 3rd level Sports Director and teacher at FCI, working in the Primavera Torino FC Health Staff
He states in summary that, assuming that the isoinertial method exploits the alternation of concentric and eccentric contraction, it produces work much more similar to a movement performed during any sporting gesture than other methods. Each technical and physical gesture is based on the alternation of acceleration and deceleration of one or more body segments, which store and return strength according to the objective.
He then adds that also in plyometrics there is an alternation of the different contractions, but in this case an overload is produced induced by the speed of execution of the gesture during the eccentric phase. All this with isoinertial machinery may not necessarily be generated, since everything depends on the speed with which the concentric phase is performed. Furthermore, in a plyometric gesture there is a greater joint overload , which can be largely limited with isoinertial training.
This aspect becomes crucial in the preventive field.
The key point of inertial training is to stimulate the athlete or user to perform a motor gesture that inevitably refers to the technical-sporting gesture. This way you can get a workout
optimal and complete in view of performance.
One of the differences with respect to work with overloads in general, unless an explosive gesture is performed, is that the force produced with isoinertial machinery is not constant but varies , exactly as it happens in reality .
In a study by Onambelè & coll. in 2008, two groups of subjects over 70 years of age were compared. These subjects were assigned a program of muscle strengthening work on the knee extensors with isoinertial and overloaded machines, respectively.
Not only did the work with the isoinertial method produce a greater increase in power in the quadriceps, but significant benefits were obtained on the myotendinous component of the plantar flexors of the foot, with an increase in balance as well.
Furthermore, in a research by Baricich & coll., Which compared training with overloads with respect to isoinertial in the execution of a Front Squat , significant differences were highlighted. In particular, during the eccentric phase, a greater global muscle activation was highlighted with electromyography.
Finally Capello concludes by stating that: the eccentric phase is the hub of the isoinertial method.
In recent years, much attention has been paid to this component of work with a view to preventing accidents and myotendon problems . This aspect is absolutely not to be underestimated, as it is known how difficult it is to emphasize with the various users the care of the eccentric phase of the movement. Often it is not considered as much as it should, but in reality it is the queen of joint wellness . During the eccentric phase it is possible to offer a great stimulus to the tendon component as a consequent support of the ligament apparatus of the various joints.
There are now several studies and researches conducted in this regard and most, if not all, show that the effects of a targeted workout on the eccentric phase offer incredible benefits in the well-being of the person. The importance of the eccentric component is evident and it would be good for all professionals to understand its importance, to aim more and more at the well-being of the person or the athlete, or of the patient in the case of a therapist.
In support of Dr. Capello's thesis we report some studies:
In 2007 Visnes and Bahr evaluated eccentric training as a function of patellar tendinopathies and highlighted how this can be functional to the cause.
In 2008 Hibbert & coll. reviewed multiple studies concerning the lower incidence of ischio-peroneo-tibial muscle injuries after a work program on eccentric contraction.
In 2014, a research conducted by Zuppardo & coll. showed that in amateur athletes the large muscle deficit in the eccentric phase can seriously increase the risk of injury to the anterior cruciate ligament (ACL) and that an isoinertial work program would be ideal from a prevention perspective.
In a 2010 study by Norrbrand, Pozzo and Tesch , it was studied how effectively isoinertial training produces more stimulus in eccentric contraction compared to a classic training with overloads. Also in this case, the researchers argue that, both in the concentric phase and in the eccentric phase, during the execution of the gesture, we have come close to producing a maximal muscle activation, greater than a classic method.
The use of isoinertial machines can be very varied and for any type of user.
The stimulus is produced exclusively by the speed of execution, as well as by the weight of the resistance placed at the base of the machine. There are no further joint overloads as they do not come
weights were used, but only resistors tied to inextensible cables. You can carry out exercises with a closed kinetic chain, optimal for example in the first phase of a rehabilitation , as well as with an open kinetic chain, to carry out multi-planar activities.
What Dr. Capello points out is that with the use of inertial training we do not want to diminish or replace any other type and method of work. This method must represent a supplement to further improve athletic training, rehabilitation and motor re-athletization.
Incorporating this new method into one's work represents an ever-increasing possibility to be able to work at its best with a view to real prevention .
The major sports stages and major clubs in Europe and the world are already equipped in this sense and over the years have found irrefutable benefits and improvements for their athletes.
The difference between the isoinertial methodology and other forms of training.
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To better understand what are the substantial differences between the isoinertial methodology and the others (in particular isotonic and isokinetic) we refer to the words of Prof. Carmelo Bosco , considered as the most important Italian researcher, not a doctor, in sports science.
He, in his text "Methods of functional testing during rehabilitation exercises", Department of Exercise Physiology and Sport Biomechanics (University of Budapest Hungary), University of Rome Tor - Vergata, Italy, School of Specialization in Physical Medicine and Rehabilitation, states that: [...] Both methods ( isotonic and isokinetic ) have the limit of inducing a muscle contraction that does not occur during the execution of any motor gesture : joint movements during normal motor tasks such as walking, running or moving external resistances do not in fact, they are performed neither at a fixed joint angle (isometric evaluation) nor at a constant angular velocity (isokinetic evaluation) […].
On the basis of the criticisms addressed to the isometric and isokinetic method, in the 90s Prof. Bosco proposed the evaluation of muscle strength in isoinertial mode. He also stated that from a neuromuscular point of view, this condition more closely mirrors the muscle contraction regime that underlies any athletic gesture typically aimed at moving external resistance against gravity (running, jumping, throwing objects, etc.).
Regarding the safety in the execution of the exercise, he stresses that overloads to the tendon structures, avoided with isokinetic systems, can be prevented by using very light loads that can be administered from the beginning of the rehabilitation phase.
On this topic it is also interesting to report the observations made by the trainer and writer GN Bisciotti in 2012 in his speech at the Faculty of Sports Sciences, University of Lyon "The isoinertial modality as a method of investigation of the biomechanical muscle function".
He underlines that the first substantial difference is constituted by the fact that, during an isokinetic movement, the muscle, contracting at a constant speed, cannot generate acceleration , which, on the contrary, constitutes one of the main characteristics of natural movement .
Secondly, it should be pointed out that most human movements are characterized by a muscle activation which involves an eccentric muscle contraction phase, immediately followed by a concentric phase ( Goubel, 1987; Komi , 1987).
This particular type of activation is commonly referred to as the shortening stretch cycle (SSC) (Norman and Komi, 1979; Komi, 1984).
It must be remembered how the muscle, during a movement that includes an SSC, is able to
develop very significant angular velocities , which can reach 15-16 rad. sec-1 (Bosco, 1982; Bosco, 1997), while the angular velocities that can be reached during a movement carried out on an isokinetic device can be at most in the order of 6 rad. sec-1.
Furthermore, even the most modern isokinetic devices allow a maximum reversal time from the eccentric phase to the concentric phase (coupling time) of about 50-100 ms, while during a SSC carried out in conditions of natural activation, the latter is of about 10 ms .
A further differentiation between the movement performed in isokinetic form, compared to the isoinertial type activation, is constituted by the different neuromuscular activation pattern .
In fact, an isoinertial movement is characterized by a strong initial myoelectric activation , corresponding to the moment in which it is necessary to overcome the inertia of the load, followed by a marked myoelectric decrease, also due to a probable inhibitory effect by the Golgi Tendon Corpuscles (Angel, 1974; Bosco et al., 1982).
On the contrary, during an isokinetic contraction, the electromyographic activity (EMG) remains substantially at the same magnitude along the entire range of motion, even if the EMG is normally recorded during an isoinertial movement, even in its phase of lower magnitude. , however, it remains higher than the EMG recorded during the same type of movement performed in isokinetic mode under the same load (Hislop and Perrine, 1967).
All these series of evaluations, as suggested by GN Bisciotti, must lead us to consider both the exercises and the isokinetic tests as an interesting method, both for work and for neuromuscular investigation, only in the first phase of a post-rehabilitation. traumatic .
The large differences inherent above all in the diversity of neuromuscular activation patterns between isokinetic and isoinertial contraction, in fact show that through isokinetic monitoring, such as the construction of the force-speed relationship, the neuromuscular framework of reference is extremely limited. In addition to this very important aspect, it is also necessary to add the lack of acceleration, which on the contrary constitutes one of the basic characteristics of the natural isoinertial ballistic movement and the consequent diversity in the neuromuscular activation patterns.
Isoinertial, from training to physiotherapy
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Isoinertial technology has been widely used in the treatment of tendinopathy. For example in chronic patellar tendinopathy using an inertial machine connected to a Leg Press (Sweden) there was a clearly positive effect on athletes ( Romero-Rodríguez et al., 2011).
Subjects reduced their pain perception (VAS scale) and improved their functional capacity by increasing strength levels and neuromuscular activation after training through eccentric overload .
The isoinertial method has also been studied for preventive purposes. In fact, Gual et al., 2016 administered a single session work protocol to volleyball and basketball players with excellent results. In the field of accident prevention many studies including Gual et al., 2016; Askling et al., 2003 and de Hoyo et al., 2016 investigated the method using the cylindrical disc.
The isoinertial force-velocity relationship as a diagnostic method, case study: the knee joint
Through his studies, Dr. Bisciotti has highlighted how the force-speed relationship built through the isoinertial method can therefore constitute an important means of information for what concerns the neuromuscular parameters typical of a natural ballistic type activation pattern.
The construction of an inertial force-speed relationship can be carried out either through a concentric-eccentric movement or through a mode that includes an SSC, monitoring muscle action across the entire possible range of force-speed relationship, in other words through all possible relationships of speed of contraction and production of force.
In the case of an isoinertial force-speed relationship built through a purely concentric movement, we would naturally have mechanical information inherent only in the behavior of the Contractile Component (CC), while in the case of a force-speed relationship built through movements involving a phase of SSC , we would also have information on the mechanical behavior of the elastic component in series (SEC), the comparison between the two curves can therefore provide important information on the elastic behavior of the considered musculature. Finally, in the case of an eccentric force-speed relationship it is possible to investigate the muscular behavior of the CC in conditions of elongation .
In the diagnostic-sports field, the force-speed relationship can give very important information, especially in the context of two main aspects:
The first, consisting of the possibility of 'biomechanically photographing' the neuromuscular behavior of a healthy muscle, in anticipation, in the event of trauma, to have, in the rehabilitation phase, a comparative of optimal muscle biomechanics to refer to during the rehabilitation phase itself. ;
The second consists of constant monitoring , always operable in the rehabilitation phase, through which it is possible to obtain data that can be used in the drafting and control of the physiotherapy phase.
Through the construction of the force-speed relationship through the isoinertial mode, it is therefore also possible to calculate the maximum theoretical power expressed during the investigated movement.
This last datum can constitute a further important parameter of evaluation and control in the functional and rehabilitative field.
The high reproducibility of the force-velocity relationship (r = 0.85-0.967) (Bosco, 1991; Bosco et al., 1995; Murphy and Wilson, 1994; Bisciotti et al. 1999) guarantees the scientific reliability of this method of investigation.
Bisciotti concludes by stating that the construction of the isoinertial force-velocity relationship therefore presents an undoubted diagnostic value in the rehabilitation field, above all for its total relevance to the neuromuscular activation patterns that are found in the course of a natural movement of a ballistic nature, typical of the gesture. sporting, relevance on the contrary ignored in the case of isokinetic type tests .
Can eccentric overload improve performance? Case study: football.
In strength training, there are many methods studied by researchers and implemented by physical trainers to improve the athletic qualities of athletes, including the isoinertial method.
In this regard, a 2018 study published by Luis Suarez-Arrones et al is interesting. , entitled In-season eccentric-overload training in elite soccer players: Effects on body composition, strength and sprint performance. The document deals with the study on the athletic preparation of a football team.
The aim of the study was to describe the changes in body composition , strength and sprint performance during an entire season in which two workouts with overload were carried out using the inertial method.
The body composition of the 14 young players who participated in the study was evaluated through DEXA, strength output and 40m sprint.
The overload training consisted of sessions in which 1-2 sets of 10 upper body and core exercises were performed on Day 1, and Lower body on Day 2; the duration of the protocol was 27 weeks.
Fat mass decreased to (-6.3 ± 3.6%, ES = -0.99 ± 0.54) substantially, in favor of lean mass gain (2.5 ± 0.8%, ES = 0.25 ± 0.09).
A substantial improvement was observed in power output on the half squat (from 3% to 14%, ES from 0.45 to 1.73) and on sprint performance and (from 1.1% to 1.8%, ES from -0.33 to -0.44 ).
A combined training of football and eccentric overload (with isoinertial method) has promoted positive changes in body composition and performance factors, both in terms of field practice and in the prevention of injuries of elite footballers.
In this regard, the vision of Roberto Sassi , an athletic trainer, emerged in an interview with him a few years ago is interesting.
Case study: football. Interview with Roberto Sassi (by F. Ferretti)
Roberto Sassi is one of the best known athletic trainers in football. In addition to many Italian Serie A teams (Lecce, Lazio, Turin, Verona, Fiorentina, Parma, Sampdoria), he also had work experience in the Premier League (Chelsea) and in La Liga (Valencia and Atletico Madrid); he is a point of reference for many of his young colleagues or aspiring ones. Mognoni said that no one as Roberto Sassi had so many tests of football players, among other things from all over the world (many of which of very high levels) and moreover performed with great rigor. His work with teams is characterized, for example, by the methodical application of dynamic stretching, by the control of cardiac commitment during exertion, by the evaluation - parallel to that of training - of blood chemistry values and so on. In this interview, in any case, we mainly talk about the new method for strength that was the first to introduce in Italy.
Roberto, in your opinion, is strength training important for the player? And if so why?
All international literature agrees that in sports games (and therefore also in football) strength training not only increases the player's performance, but also prevents injuries. [...] The most important concept is that which concerns the muscular mechanical power, that is to say the ability of the neuromuscular system to exercise the maximum expression of muscular movement, in which there is the interaction between maximum strength and maximum speed possible. Muscle mechanical power, calculated as a product of strength x speed, is one of the factors that most of all affect the performance of any athlete. [...]
Is it true that you no longer use some of the traditional means to train strength?
Traveling around the world, going to conferences, exchanging opinions with colleagues from various countries and working in the field, I gradually became convinced. For the arms and trunk I still use the barbells, as well as I work in the classic way on the abdominals and backs, with the aim of stabilizing the torso. To improve the strength of the lower limbs, however, I no longer use the wood jumps or obstacles, but neither do I use strength machines, built for the fitness of normal people. They are all undoubtedly effective means, but now there are machines that allow for greater improvements and with which, we notice an improvement in the leap ability in players who, mind you, have never jumped during training.
[...] Certainly this new method creates less muscle damage and quite possibly prevents them.
The players who have worked with this method in the last three years have had no hamstring or tendinitis injuries.
Why, in your opinion, is there a feeling that muscle injuries tend to increase in this period?
From my data it appears that for sure in our Serie A there is an increase in muscle injuries. The reasons, in my opinion, are at least three. The first is that, before each session (even when you do two a day) there is no effective warm-up. Or, perhaps, it should be said that with players (but the same goes for athletes of other sports), one does not educate in muscle prevention. The second reason concerns precisely the work for the force. All preparers and numerous scientific articles argue that strength training is an important aspect for injury prevention; but if the muscle injuries increase, it means that we do something wrong in the training methods. Personally I think eccentric work is very important. [...]
How did you get to know these new methods of working for strength?
[...] In Spain, on the other hand, I had very interesting and very useful exchanges with the sports technicians of that country which, not surprisingly, achieves high level results in many different sports. At a congress I also had the opportunity to get in touch with the Spanish working group led by Julio Tous. In this way I was able to know the methodology of working with special machines for eccentric strength training. With Tous I then established a relationship of friendship and collaboration and, later, I got the company to add him to the staff of external collaborators of the first Sampdoria team in 2006-2007 when I was their trainer.
Can you explain to me in a simple way the working principle of these machines?
Curiously, this technology was initially born in collaboration with NASA to allow astronauts to train in space by preventing atrophy in postural muscles (not used in the absence of gravity). Subsequently, its potential in the application in the sports sector was discovered and it works like this: during the concentric phase of the exercise, the muscle is contracted with the maximum possible force by pulling a belt rolled on the axis of a flywheel which, in this way , it starts rotating at high speed. The strap is long enough to be fully unwound at the end of the movement. Due to its inertia the flywheel continues to rotate, rewinding the belt in the opposite direction, thus pulling the limb towards itself. Thus begins the subsequent eccentric phase of muscular work. In other words, after a slight initial resistance, the subject begins to brake, pulling the belt until the flywheel stops completely. When he starts pulling again, he starts the next repetition and so on for the duration of the exercise. It becomes possible to increase or decrease the inertia by mounting a greater or lesser number of flywheels: a greater inertia is more suitable for work with maximum force, while a lower inertia involves much faster (and in any case maximum) movements and is more suitable for the development of explosive force.
What is the main difference from conventional exercises?
One of the main differences compared to conventional exercises (weight machines, barbells or dumbbells) is that, while with weights the resistance is constant and equal to the set load (isotonic exercise), in isoinertial devices the resistance is adapted at all times, and proportional to the developed force: the greater the force, the greater the acceleration with which the flywheel reacts (isoinertial exercise). This working method exactly reproduces the situation in which the muscle works during sports activity: at variable strength and speed, and accelerating and decelerating an inertial load (such as the ball, a limb, the body itself during a sprint). Furthermore, since the resistance is proportional to the effort developed, each repetition can be carried out at the maximum possible strength and, contrary to traditional weights, it is by definition maximum (although with decreasing strength due to fatigue). The result is a greater training load with the same number of repetitions - and therefore greater performance.
Are there any other advantages of using machines with an isoinertial system?
The main advantage is the possibility of developing a so-called eccentric overload, that is a greater peak force and power in the eccentric phase (precisely, the one with the greatest risk of injury) than in the concentric phase. In practice, during the concentric phase the flywheel is charged with energy (kinetics), and this energy is fully returned during the following eccentric phase. If the braking is delayed in this phase, leaving the belt to rewind initially without resistance, the duration of the active eccentric phase will consequently be reduced. As a consequence, the developed power (that the ratio between the energy and the time in which it is developed or absorbed) will be greater. By controlling the duration and intensity of the braking phase, it is therefore possible to reproduce an eccentric overload similar to that to which the muscle is exposed in playing conditions. This obviously presupposes the use of suitable equipment to measure this overload and provide feedback to the player to allow him to work under controlled conditions. [...]
What types of injuries have you had using this methodology?
The aforementioned eccentric training - consisting of exposing the muscle, under controlled conditions, to high eccentric loads - is currently recognized as the most effective method of injury prevention. From a practical point of view, the use of isoinertial machines, when combined with other work strategies, showed a decrease of 19% on muscle injuries and 33% on all types of injuries in a professional football team. There is a large scientific literature to document the effectiveness of this methodology (for those wishing to deepen, I point out among the various authors: Berg, Tesch, Dudley, Trappe, Alkner, Pozzo, Tous, Fluckey, Narici). Last season, with the Primavera team, while training on synthetic pitches and playing on grass pitches, we only had one muscle injury (rectus femoris), but, above all, in the two years in which I used this methodology I had no injuries muscle to the hamstrings.
Besides Sampdoria, which other teams in Italy have used this work?
After I talked about it, Fiorentina, Lazio and Sassuolo adopted him. Many of the best European teams are also users of these machines. To name a few: Barcelona, Deportivo La Coruña, Porto, Liverpool, Ajax, Le Mans ...
With these machines, how much work do you have to do in each session?
In a team of young people, I have two sessions per week done; the first consists of three circuits of 10-12 stations, of which three with isoinertial machines. Each of the three circuits lasts approximately 15 minutes. The second session, on the other hand, is 1 or 2 circuits.
Figure 1. Increase in muscle mass over a competitive season in a Spring category team
Figure 2. Representation of the height in the vertical jump test (carried out using a Kistler® dynamometry platform which allows to directly measure the forces applied by the athlete and therefore the power developed during the test) of the players of the spring team from July 2007 to March 2008. (*; p <0.05; Significantly higher value than the other two tests performed in July 2007 and December 2007)
Figure 3. Representation of the power developed in the vertical jump test (again carried out using the Kistler® dynamometry platform) of the players of the spring team from July 2007 to March 2008. *; p <0.05; Significantly higher than the test carried out in July 2007
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NOT ONLY SPORT
Rush is the auxotonic Spacewheel machine for
training and rehabilitation
Possibility of working up to a maximum of 24 meters
distance from the car
Easy modulation of workloads
Up to four working points simultaneously
INFINITY
columns for space optimization
DYNAMIC
from training to physiotherapy
The Dynamic series is the Spacewheel isoinertial machine line, intended for all phases of physical activity: from preparation to rehabilitation.
The isoinertial exercise involves an improvement of the coordination functions of the body and a complete training in both the muscle stretching phase (concentric phase) and the contraction phase (eccentric phase)
RUSH
effective and safe auxometric training
The Infinity series is the Spaceweel line of isoinertial columns, intended for all phases of physical activity, for the whole body.
Infinity was born for the optimization of the workspace.
With its extremely versatile models it is also possible to work in two at the same time.